Rock drill



April 2, 1929- J. msn-:BERT Er AL ROCK DRILL Filed July 24, 1926 f l l I l l l l II\IIIII|IIIIIII|NIIIIIIXHV/J 7 .0 ,.w wm .mw Qn/ T E: gfx .EN mw a *Q Y \\w N w8 m 4 Il N Tur. Il l JA@ l1 *44| I| Il: u A Q ,T11

Patented Apr. 2, 1929.

UNITED STATES PATENT oFFlci-z.A

y JOHN MARTIN SIEBERT AND GEORGE LAWRENCE WARREN, OF JOHANNESBRG,

. TRANSVAAL, SOUTH AFRICA.

Rocx DRILL.

Applircationled J'uly 24, 1926, Serial No. 124,728, and in the Union of South Africa September 23, 1925.7

This invention relates to krock-drills or rock-drilling machines of the hammer piston type. Y

One object of the invention is to provide suoli a machine with a means which Vwill operateto centre and steady the drill, bit or steel, when it is placed in position Vin the chuck, rotation sleeve or tool holder of the machine, and so obviate breakages vof the steels or drills that frequently occur due to` vibration arising from the fact thatA the drill or steel is not properly centred and steadied.

Another feature relates in particular to a hammer piston drill provided with means for supplying water to the cutting points of the steels, drills or bits used With such machines, in which the water is conducted by means of a water tube which extends axially through the cylinder and hammer piston to the rear end of the drilling machine, at which point the water supply enters the tube. lVith this kind of water supply attachment ditliculty is experienced in maintaining the water supply tube central or truly axial, with the result that breakages of the tube frequently occur or excessive wear takes place, which results in the entrance of-air into the water passage occasioning dispersal of dust into the atmosphere and also leakage of the water into the cylinder and other parts of the machine.

Further objects ofthe present invention are, to construct the rockfdrill, the steel, drill or bit, and the water conveying tube in such a. way that the latter' will be automatically centred or maintained in a position axially of the drill when it is placed in the chuck, rotation slee've or holder, and so obviate breakage of the water tube; and to prevent the passage of air into the water tube aud/or drill, steel or bit, and the entrance of water into the cylinder of the machine.

The invent-ion will be fully explained in connection with the accompanying sheet of' drawings, wherein,

Fig. l is arpartsectional velevation of a rock-drilling machine of the hammer piston type, incorporating the invention.

Fig. 2 is a. part-sectional elevation, drawn to an enlarged scale, of the rear portion of the steel, drill or bit and the water supplying tube, illustrating the means for making the joint or connection between the said parts.

Fig. 3 is a half-sectional elevation of a holsteel or bit, and serves for centering and steadying the end of said drill, steel 0r bit,

vand

Fig. 6 is a half-sectional elevation of a .modified form of said loose or floating member. 1

In Fig. 1 the numeral 1 denotes the rockdrill or rock-drilling machine, 2 being the front head and 3 the chuck or rotation sleeve. 4 is the water supply tube which is arranged axially of the machine 1 and into the rear end of which the'water is conducted through the connections 5.

6 represents the hollow steel, drill or bit- See also` Fig. Q-into the rear end of which the forward end of the water tube 4 projects so as to deliver the water into the hole'7 provided axially through the drill, steel or bit 6. The forward end of the water tube 4 is tapered as indicated at 8, and at the rear of said tapered portion it is provided with an enlargementV forming an annular shoulder 9. Around the water tube 4 at the rear of the shoulder 9 is arranged .the tapered rubber or other resilient piece or sleeve 10-see also commodate said sleeve 10 .and the enlargedy end 9 of the water tube 4. The bush or tubular piece 11 facilitates theintermittent rotary movement of the drill 6, together with the rubber sleeve 10, around the water tube 4.

The passage of water in a rearward direction and of air in a forward direction between the tube 4 and drill, steel or bit 6 is prevented by the rubber or like sleeve 10, so

CII

that the leakage of air into the hollow drill' 61 or Water into 'the cylinder oi' i the` machine is obvia'ted.

The extremity of the shank or rear end of the bit or steel 6 is rearwardly tapered, and

in 'placing the same in'position it is'pro? jeeted through the chuck bush or' liner 13 over the enlargement 9 on the forward endl olthe Water supply tube 4, as shown in Fig. l.

The chuck, rotation sleeve or holder 3or the drillor steel is provided with loose or floatingl piece'or nieniberlt.' lnFigs; lfafnd" the 5 member 'lil is 'l shown constructed' iior use in an existing chuck (ii-rotation? sleeve, it

being` made oit tWo different diameters externelly, the Cylindrical portion of largerfdiameter loosely litting the enlargedforward por- 'A tion olthe bore of the Vchuck;fandthersheulder foi-med between said portionfand the rearv smaller cylindricalJpertioii enga-ging the pro- .;jeetionsformedf bythe 'lironthends' eifthe ety the rotationl sleeve'. 3. snialler cylindrical `portion or thefmeniber le v nro'ieets rearwardl f `into the ilutedfiertion of therotatieii sleeve 3, as showin infFig. l.

' Through the member le a tapered hole 16 is formed which lits: the Itapered `rear' entreinitjyY asshown inl@1 I to receive the impacts oli4 oli-tliedrill, steel er bit (i, the rear endet the latterlirogecting through to the requr teen- 'tent beyondtherear end ol said member ill `the hammer piston 17. Y T he bush V(ir-"linerl3,fwhieh is fixed in* the `rotation sleeve 3, is shaped interiorly closely Y to lit-the shank or the drill or steel G, infront of the tapered rear end portion, and trans` i initsfthe rotary` motionE from' thechuck or rotation sleeve 3 tothe drill or'steel The rotation lsleeve 3, as shown, iis prefer 'ably v'constructed `Withfian` external annularV groove 13Whieh communicates byineans or ytiansrerse Vholes 19 with the-interior 'or said sleeve,v and,'throughl the 'furthewheles QOin Y tliefrent'head, with the o'the escape ofany exhaust air that may lealr'inte the rotation' sleeve 3.

1lllflicn'theidrill or'steel G is projected bore ofthe bit, and Va buslipositioned mediate the"resilientfsleeve and the Water atmosphere to fallow through the eliuek bush 13, the tapered inner rendi of 'the drill; enters i' the 'eeri'espoirdingly tapered holethroughlthe yloose or'tloating member le and is lthereby centred or brought into axial alignment Withthe Water tube 4l. rthismember 145 also operates to stead?,7 the drill or steel 6 when the machine is in operation, and by minimizing Vibration iirevents c breakage of the drill or'steel trom that cause.

i ln' Fig. 6 We: illustrate `a diiiferen't Yterni" oi the member 14j. In this ease it is et cylindrical shape or o'l'iinife'rni'eizternal diamete lfrom endl tof l end. i lt Wi ll be raidapted'- to 2 i'it a rotation sleeve Constructed eorrespond.-

flvhatweclaimas our invention and desire to' protect by'lLetters Patent is 1 E l. Thecoinbination Wth a roeledrilling interiorly to yfniaehiiie', including;v aftoo'l holder, a 'water supply tube andE a 'hfo'llow bfitz having a tapered v shank', of 'aj looseE itlo ating' member arranged in and loosely*iittingithe-teol holderfaiid adapted to move longitudinallythereof, and

tapered interiorly to receive the-tapered I shank of the bit-,fa resilientsleeif'e arranged around the Water tube 1 and f tightly fittin'oy 'the tersupply tube, as set forth.

2. Theleombination with a rock-drilling' machine, including aftool holder, Va Water ,supply Jtube and aliolloW bit hang a tapered shank, of aA loose' lloatiiignioniber arranged in, unconnected with` and looselfrlieting" the 'Y tool helder and vadapted te more longituc ishanland tightly ttingthefbore of the bit,

as set forth.

- ln testimony'whereof Weliavesigned our names rto this sliieeieation.

g Joris Miin'riir sinnnpafr.

Geenen LAWRENCE Viii/ninna 

